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Using open input schmitt trigger CMOS logic as "soft latch"?

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ELS122:
I'm looking for the simplest circuit to latch an output to be pulled low, or be open (or pulled high)
With the circuit keeping it's previous state when the input is open circuit.
Then to switch states just pull the input pin low or high.
Like the behavior of the circuit I attached

Would a CMOS Logic inverter with a schmitt trigger have this behaviour? If the input is open will it retain it's previous state?

For multiplexing LED's without needing to drive tons of peak current trough them to retain apparent brightness

Kim Christensen:

--- Quote from: ELS122 on September 24, 2023, 03:05:21 am ---For multiplexing LED's without needing to drive tons of peak current trough them to retain apparent brightness
--- End quote ---

But then you need a latch for each LED, so you're basically back to direct drive.
ie: Just use a LED driver IC with a serial interface. Or make your own with a shift register/latch combo. (74HC595)

ELS122:

--- Quote from: Kim Christensen on September 24, 2023, 03:15:58 am ---Or make your own with a shift register/latch combo. (74HC595)

--- End quote ---

As if that wasn't the question.

soldar:

--- Quote from: Kim Christensen on September 24, 2023, 03:15:58 am ---But then you need a latch for each LED, so you're basically back to direct drive.
--- End quote ---
Maybe I am missing something but this does not make sense to me.
If each LED has its own latch then it can be set and will stay in that state until changed.
In a matrix row after row can be set and will remain in state indefinitely.

Kim Christensen:

--- Quote from: soldar on September 25, 2023, 07:53:02 am ---Maybe I am missing something but this does not make sense to me.
--- End quote ---

Yup... It makes no sense to me either. It reads like the OP wants to multiplex LEDs without multiplexing them.  :-//
See quote below:


--- Quote from: ELS122 on September 24, 2023, 03:05:21 am ---For multiplexing LED's without needing to drive tons of peak current trough them to retain apparent brightness
--- End quote ---

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